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Topic: screen bottom (Read 3819 times)

hello everyone. im building a top bar and have a question about the bottom. i live in oklahoma where the summer temps are around 110 and its really windy, normally 20+ winds.what type of bottom should i have? screen or a board? if screen can i use window screen?

A SBB will give you better ventilation if you make the pan only as long as the hive. The screen has to bee #8 wire cloth. The reason is that it keeps the bees out of the oil pan and let's the beetles fall into the oil. I put window screen under the pan to keep the bees from getting into the pan from the bottom and allows air in the front under the landing board. With 110 degree temps, I would add a screen top board (STB) and metal backed foam under the cover. This will keep the temps in the hive down.Jim

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The brood nest has to be 93 F. No more. When it's 110 F outside, that means they have to cool it by evaporating water and controlling the air flow. Do you leave the door open when the air conditioner is running?

The brood nest has to be 93 F. No more. When it's 110 F outside, that means they have to cool it by evaporating water and controlling the air flow. Do you leave the door open when the air conditioner is running?

But Michael, air conditioners and evaporative coolers are two different things....you've gotta have ventilation with evaporative coolers or you end up with a very humid mess. Whether you need the entire bottom of the hive open or not, I don't know...I'm still learning. :)

Ed

ETA: I just re-read the op's post and he mentioned winds of normally 20mph....I don't think he'd have problem doing air exchanges with solid bottom board with that kind of wind. Down here in the deep south when have a lot of hot humid windless days so not too sure about the air exchanges here.

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I am completing my first hive. I have watched all the videos I could get my hands on....I found two schools re: bottom screen. One says a solid board across the bottom the other says screening.....I installed screening and made up a board which mounts over the screen thinking when it starts to chill the board gets mounted. I have not been able to get any more info besides a reply above with the desired temperature. Is the temp a not exceed number at all costs or a relative guide? I live in mid Michigan and we get some warm summer (100f) days and some terribly cold winters (-10 f - -15f) Any advice for this new bee ?

>But Michael, air conditioners and evaporative coolers are two different things....

Yes.

>you've gotta have ventilation with evaporative coolers or you end up with a very humid mess.

Yes, but with too much ventilation you will always end up with the same temperature as outside or, due to the sun and heat from the bees, hotter. You CANNOT keep it cooler than outside (which is necessary if the tempearture outside is above 93 F) if you have too much ventilation. You also cannot keep it cool if you have too little ventilation.

>But Michael, air conditioners and evaporative coolers are two different things....

Yes.

>you've gotta have ventilation with evaporative coolers or you end up with a very humid mess.

Yes, but with too much ventilation you will always end up with the same temperature as outside or, due to the sun and heat from the bees, hotter. You CANNOT keep it cooler than outside (which is necessary if the tempearture outside is above 93 F) if you have too much ventilation. You also cannot keep it cool if you have too little ventilation.

Makes me wonder why external colonies hanging in oak trees, under roof overhangs, or wherever do not die out when they are subjected to extended ambient temperatures well above 93F in the summer. They have no control over ventilation. :?

Ed

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www.beeweather.comAmerican blood spilled to protect the freedom and peace of people all over the world. 320,000 USA casualties in WWI, 1,076,000 USA casualties in WWII, 128,000 USA casualties in the Korean War, 211,000 casualties in the Vietnam "conflict", 57,000 USA casualties in "War on Terror". Benghazi, Libya, 13 USA casualties. These figures don't include 70,000 MIA. But, the leaders of one political party of the United States of America continue to make the statement..."What difference does it make?".

"We can't expect the American People to jump from Capitalism to Communism, but we can assist their elected leaders in giving them small doses of Socialism, until they awaken one day to find that they have Communism."..."The press is our chief ideological weapon." - Nikita Khrushchev

i use solid bottom and a 10 x 1 cm main entrance + upper entrance 1.5 cm .In Langstroth that is 5% that of mesh floor area.During main yield period openings must be wider.

Where the 95% ventilation is needed outside of main yield period?

I look the need of ventilation from number of ventilating bees..

Finski, lowering the windows is one of the first things we do when we get into a hot car...it really seems to make a big difference when a car has been sitting in 100F+ degree sun. Some people have non-working a/c units...they certainly don't ride around in the summer with their windows rolled up...there must be a reason that they roll them down....maybe to allow the absorbed heat to escape and maybe to get some evaporative cooling going on via their sweat and the wind created as they travel down the road?

I'm not arguing the point that bees know and are capable of controlling a good bit of their immediate environment. It is some of the reasons and whys given that I wonder about. With my tiny newbee mind I'm wondering whether the evaporative cooling process happens in close proximity to the comb and whether the drop in temperature in empty cavity space is a byproduct of cooling the comb/brood/honey (convection?), and that bees around entrances fanning are doing some to evacuate moisture moreso than heat. External colonies would only be concerned with the area immediately around the comb...they have no cavity with a certain size opening to regulate...their entire surrounding is more open than a screened bottom board...and they apparently handle the heat...somehow.

You and Michael both know much, much more than I will ever know about bees and I greatly respect ya'll and appreciate ya'll sharing your knowledge, but...I still have to ponder over things. ;)

Ed

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www.beeweather.comAmerican blood spilled to protect the freedom and peace of people all over the world. 320,000 USA casualties in WWI, 1,076,000 USA casualties in WWII, 128,000 USA casualties in the Korean War, 211,000 casualties in the Vietnam "conflict", 57,000 USA casualties in "War on Terror". Benghazi, Libya, 13 USA casualties. These figures don't include 70,000 MIA. But, the leaders of one political party of the United States of America continue to make the statement..."What difference does it make?".

"We can't expect the American People to jump from Capitalism to Communism, but we can assist their elected leaders in giving them small doses of Socialism, until they awaken one day to find that they have Communism."..."The press is our chief ideological weapon." - Nikita Khrushchev

Ahhh, but they do, if there isn't too much. Huber's research showed that ventilation was less with more openings than the standard one (this was in a skep, not a Langstroth and there was no top entrance), so I think having the entrances such that the bees can CONTROL the ventilation is more important than having a lot of opening. Bees fan to control ventilation. They control the actual path of the air as well as the volume with fanning bees.

Ahhh, but they do, if there isn't too much. Huber's research showed that ventilation was less with more openings than the standard one (this was in a skep, not a Langstroth and there was no top entrance), so I think having the entrances such that the bees can CONTROL the ventilation is more important than having a lot of opening. Bees fan to control ventilation. They control the actual path of the air as well as the volume with fanning bees.

Ahhh, but how can they control ventilation when an external colony can have no walls nor floors nor ceilings nor entrances? The partial quote that you've shown is out of context with the rest of that post. Good response for a closed cavity but I don't think it works for an external colony. :)

I'm not arguing the point whether bees can and will control ventilation within an enclosed cavity...I did a cutout last year on a colony where the cavity was a sandwich of two 4x8 pieces of plywood. The colony was at the top corner on one end, at the other end a piece of channel iron made the top frame piece...at the opening in the end of this iron bees were fanning/ventilating the cavity though the colony was 8 feet away. So yes, I believe they can and will control the ventilation to the best of their ability.

What I'm trying to get at is whether there is a more micro aspect of the cooling process...that the evaporative cooling takes place at the surface of the comb and that any cooling of the rest of the cavity is incidental. The only way an external colony could cool down would be doing it this way being as any slight breeze that came along would rid them of any cool air floating outside of the thin boundary layer of air surrounding the cluster/comb.

On a somewhat related topice, something that continually amazes me is that the bees can work honey down to 18-percent (and less) moisture content in an environment that regularly ranges from 30-50 percent humidity. Amazing creatures.

Whatever the case, the bees have been surviving regardless of what we do...God's will they will continue to. :)

Ed

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www.beeweather.comAmerican blood spilled to protect the freedom and peace of people all over the world. 320,000 USA casualties in WWI, 1,076,000 USA casualties in WWII, 128,000 USA casualties in the Korean War, 211,000 casualties in the Vietnam "conflict", 57,000 USA casualties in "War on Terror". Benghazi, Libya, 13 USA casualties. These figures don't include 70,000 MIA. But, the leaders of one political party of the United States of America continue to make the statement..."What difference does it make?".

"We can't expect the American People to jump from Capitalism to Communism, but we can assist their elected leaders in giving them small doses of Socialism, until they awaken one day to find that they have Communism."..."The press is our chief ideological weapon." - Nikita Khrushchev